It has worked on cat urine smell that was impenetrable to removal by every commercial preparation on Petco's shelves AND to Oxy Clean.

I saw the episode where they tried it on skunk odor ( and it was effective ) and thought, if it works on that, how would it work on old cat funk? It worked WONDERS! I didn't have to throw out a pet carrier I was THISCLOSE to throwing out! We were at our wits end!

MythBusters, the hydrogen peroxide mix was found to be the most effective smell removal agent.[6]

From Popular Science Aug. 1995, chemist Paul Krebaum provided the recipe for the bathing concoction. One quart of 3% hydrogen peroxide, one quarter cup of baking soda, and one teaspoon of liquid soap. then rinse with tap water. There is no way to store this potion. If you put the ingredients in a bottle, the whole thing would explode.

If the cat is still urinating outside the litterbox after a couple of days she really needs to take it to a vet as the stress of the move may have predisposed it to a urinary tract infection.

Peeing outside the litterbox is the hallmark symptom of cystitis, and could indicate either minor or major kidney problems, too.

It won't allow me to post the wikipedia or mythbusters links below

EDIT: I had ALREADY STATED that every odor removal product available at PETCO had NOT worked when I tried the method I recommend, and that INCLUDED Simple Solution Cat Spray & Urine Stain & Odor Remover that was posted AFTER my entry. I also purchased every odor removal product for sale at Wal Mart. I had a cabinet full of ineffective products before I discovered the best solution. I had well over $100 on various products. I had a male cat with kidney failure who urinated in inappropriate places before he died. The only thing that worked with 100% efficacy was the baking soda/peroxide mixture. There may be fabrics that it could bleach so be careful.

I found other uses for those pet odor removal products, however. They were effective for trash can odors and they were also useful for my husbands muddy work boots..and son's sweaty sneakers. They were ineffectual for cat urine smell. I have a sensitive nose for odors.

BEFORE you waste your money purchasing products that don't work..try the more inexpensive method and I KNOW you will be happy with it!